The invention relates to a media dispenser for solid or fluid media i.e., gaseous, liquid, pasty, creamy or powder/bulk media. The dispenser is held in one hand and simultaneously actuated for discharge. It can be made for only a single medium discharge on a return stroke. Most, if not all, of the dispenser components are injection-molded or made from plastics material.
A pair of shaped elements such as a support and an insert countersunk in the support are formed around a shaping axis and a duct axis is oriented transverse to the shaping axis. After congealing these molded elements are withdrawn from the mold in a direction parallel to a mold axis. The function of the shaping elements is to guide the medium flow parallel to the duct axis. Such shaped elements may be provided at any location in the dispenser, e. g. as two housing parts of a pump, of a valve, of a piston unit, of a discharge head or the like or they may be two valve bodies. They may also be sections of a medium conduit. As regards further features and functional details incorporated in the present invention, reference is made to U.S. Pat. No. 6,257,461 issued Jul. 10, 2001.
An object of the invention is to provide a dispenser which obviates the disadvantages of known constructions.
Another object is to provide a dispenser simple to manufacture or to assemble.
A further object is to enable to collect different medium flows or media.
Still another object is to achieve smooth transitions between adjoining exterior faces of the shaped elements.
Another object is to enable atomization of the medium.
According to the invention, an insert, such as a nozzle cap, is inserted into a support, such as an actuator cap, in a direction transverse to the medium duct which traverses the insert. The two shaped elements may be manufactured in one part, in a common mold, in direct interconnection or as separate parts. The elements include first and second duct conduits e.g. so that these conduits traverse gaps or joints between the two elements. Each of the conduits may guide flows of any of the cited media, i.e. the first conduit is provided for a non-gaseous medium and the second conduit for a gas, such as air. Thus these two media are fed transversely to each other, mixed and then discharged to the environment downstream thereof.
The molded elements contact faces or tensioning faces sealingly contacting each other, are oriented transverse to the duct axis and surround this axis to provide a seal. On assembly, the contact faces slide on each other with increasing compressive tension until a firm seat is attained in the end position. Thus a self-locking rigid seat is attained simply by frictional connection and without any additional positive locking or snap members. The two contact faces may commonly form length bounds of the second conduit and may be traversed by the first conduit.
The insert has larger exterior faces transversely connecting to edge faces. One of these exterior faces may be entirely without contact relative to the support. For that, the other and remote exterior face is a rail-shaped positive-locking profile to be engaged with a counter member of the support. Thus only a single degree of motion freedom exists, namely, in the insertion direction of the insert. In all other directions the guidance and connection is accomplished with zero clearance between the faces. Thereby one of the two elements has spaced apart and juxtaposed projections. Each of these projections forms an engagement as described without motion or play in a counter profile of the other element. Thus strength and sealing are increased. This is also achievable whenxe2x80x94prior to insertionxe2x80x94contact faces are provided on the two elements with some portions of these opposable faces being aligned and with other portions being mutually and transversely offset. Thus, on insertion, the aligned faces guide the offset faces to cause the latter to slide on each other with high compressive tension.
Three or more shaped elements of the cited kind may also be provided and assembled as described. Thereby one element may be both a support and an insert, i. e. located between a further insert and the support. In production, or at the start of assembly, these elements are mutually lined up and interconnected parallel to the insert direction or in one part. Thereafter they are telescoped parallel to the shaping axis of the largest of the elements or of the main support.
The dispenser has a flow-obstruction port or damming passage to boost the medium pressure. The damming section is commonly housed by the insert and the support. The damming section is a throttle cross-section or a valve of the second conduit and is located between insert and support or between two inserts.
The bounds or the movable respective resilient valve body of the damming section may be constructed in one part with one or all shaped elements.
The second pressure chamber is located entirely within the support. This chamber is bounded by a piston which is movably mounted relative to the support, preassembled with the support and then combined with the remaining dispenser assembly. Thus a discharge head and the piston are a unit which may be axially mounted on a pump casing whereby the piston is automatically secured and locked against axial withdrawal from this casing. Then the piston can perform the actuating or stroke relative to the head. The pressure chamber of the thus formed pump directly adjoins the gap between the contact faces of the support and of the insert. Axial locking of the piston is done directly on a retaining member, such as a crimp ring, fixedly or tensionally connecting a pump housing of the first compression chamber to a reservoir.
To achieve a sufficiently high pressure, especially gas pressure, in the second pressure chamber the end wall thereof, which opposes the piston, is axially set back relative to the medium outlet or the duct axis thereof. Thus in the relatively small second pressure space a high compression is achieved up to full-contact abutment of the piston on the end wall.
To further boost the pressure of the medium in the second conduit a prestroke may also be provided which initially compresses only the second medium, whereafter the first medium is compressed and delivered together with the second medium into the cited conduits.